1. Field of the Invention
The present invention relates to an array substrate, a display panel including the array substrate, and a method of manufacturing the array substrate. More particularly, the present invention relates to an array substrate having a color filter-on-array (COA) structure, a is display apparatus including the array substrate, and a method of manufacturing the array substrate.
2. Discussion of the Background
In general, a COA-type liquid crystal display panel includes an array substrate, an opposite substrate facing the array substrate, and a liquid crystal layer interposed between the array substrate and the opposite substrate.
The array substrate includes a plurality of pixels that displays an image. Each pixel includes a gate line, a data line, a thin film transistor, a pixel electrode, and a color filter. The gate line and the data line receive a gate signal and a data signal, respectively, and are connected to a gate electrode and a source electrode of the thin film transistor, respectively. The pixel electrode is connected to a drain electrode of the thin film transistor and outputs a pixel voltage. The color filter is arranged under the pixel electrode and displays a predetermined color using a light. The pixel electrode is connected to the drain electrode of the thin film transistor through a contact hole formed in the color filter.
The color filter may be a red filter, a green filter, or a blue filter. Since the material characteristics of the red, green, and blue filters are different from each other, the exposure amount required for a contact hole to be formed through each differs, even though the contact holes are formed under the same process conditions. Thus, the sizes of the contact holes are different in the red, green, and blue filters, and if the size of a contact hole becomes too small, the drain electrode of the thin film transistor may not be exposed. As a result, the thin film transistor and the pixel electrode may be insulated from each other and an abnormal image may be displayed.